Near-infrared wide-spectrum absorbing metal complex and preparation method thereof

Abstract

The present application relates to the technical field of near-infrared spectrum absorption material, and particularly relates to a near-infrared wide spectrum absorption metal complex and a preparation method thereof. The chemical formula is [CuI(Phen)2]·I, wherein Phen is o-phenanthroline; belongs to triclinic system, space group is P -1, and cell parameters are: a =11.9194(3) Å, b =12.1217(3) Å, c =23.7593(6) Å, α =83.3830(10) °, β =77.6190(10) °, gamma =89.6640(10) °, V =3330.03(15) Å 3 . The optical absorption band of the complex extends across ultraviolet, visible light and near-infrared light regions, and the absorption band edge extends to 1600 nm, and has typical near-infrared wide spectrum absorption characteristics.

Description

Technical Field

[0001] This invention relates to the field of near-infrared spectral absorption materials technology, and in particular to a near-infrared broadband absorbing metal complex and its preparation method. Background Technology

[0002] Broad-spectrum absorption small molecule materials refer to organic small molecule-based compounds that exhibit strong and continuous absorption capabilities in the ultraviolet, visible, and near-infrared range. Compared with polymer materials, they have advantages such as well-defined structures, ease of purification, and high batch-to-batch stability, and have become a research hotspot in the fields of materials chemistry and optoelectronics. They show great application potential in areas such as solar cells, broadband photodetectors, solar photothermal conversion and environmental remediation, and biomedical applications.

[0003] However, the design and synthesis of near-infrared broadband absorption small molecule complexes still face numerous technical challenges. Existing complexes of this type generally have significant shortcomings: most complexes struggle to achieve both broadband near-infrared absorption and high absorption intensity, exhibiting low molar absorptivity in the near-infrared region and insufficient photon capture efficiency; precise control of the absorption band is difficult, making it hard to achieve continuous broadband absorption in the near-infrared region, and absorption peak shifts are common, failing to meet practical application requirements; some complexes require complex preparation processes and demanding reaction conditions, rely on noble metal catalysis, resulting in high preparation costs, and lack sufficient functional integration, making it difficult to meet the requirements of high-end devices and complex application scenarios. Furthermore, at the molecular design level, achieving broadband near-infrared absorption often requires balancing the relationship between conjugated chain length and molecular aggregation effects, as well as donor-acceptor structure and solubility, further increasing the difficulty of developing novel complexes.

[0004] Therefore, in view of the above-mentioned problems of existing near-infrared broadband absorbing metal complexes, it is necessary to develop a novel near-infrared broadband absorbing metal complex with continuous absorption band, high near-infrared absorption intensity, simple preparation process and controllable cost, and at the same time provide an efficient and easy-to-operate preparation method to solve the technical pain points of the existing technology, such as high design and synthesis difficulty, uneven performance and insufficient practicality. This has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a near-infrared broadband absorbing metal complex and its preparation method, so as to solve the problems existing in the prior art.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: One of the technical solutions of this invention provides a near-infrared broadband absorbing metal complex with the chemical formula [CuI(Phen)2]·I, wherein Phen is o-phenanthroline; The near-infrared broadband absorbing metal complex belongs to the triclinic crystal system, space group [missing information]. P -1, the unit cell parameters are: a =11.9194(3) Å, b =12.1217(3) Å, c = 23.7593(6)Å, α = 83.3830(10)°, β = 77.6190(10)°, γ = 89.6640(10)°, V =3330.03(15) Å 3 .

[0007] In this invention, near-infrared broadband absorbing metal complexes are found in triclinic crystal systems. P Crystallized in space group -1, each unit cell contains six molecular formula units. Each copper ion exhibits a tetrapyramidal five-coordinate configuration, coordinated with four nitrogen atoms from two phenanthroline groups and one iodine atom. There is also an I... — It exists in the crystal lattice as a counter anion.

[0008] The second technical solution of the present invention provides a method for preparing the above-mentioned near-infrared broadband absorbing metal complex, comprising the following steps: Cuprous iodide, o-phenanthroline, solvent and hydroiodic acid were mixed and reacted to obtain a near-infrared broadband absorbing metal complex.

[0009] In a preferred embodiment of the present invention, a mixture of cuprous iodide and o-phenanthroline is first dissolved in a solvent, then hydroiodic acid is added dropwise, and then the mixture is further transferred to a sealed container for reaction. After the reaction is completed, the temperature is lowered, and dark brown blocky crystals precipitate, which is the near-infrared broadband absorbing metal complex ([CuI(Phen)2]·I).

[0010] In a preferred embodiment of the present invention, the molar ratio of cuprous iodide to o-phenanthroline is 1:1 to 2, for example, it can be 1:1, 1:1.5 or 1:2.

[0011] In a preferred embodiment of the present invention, the ratio of cuprous iodide to solvent is 0.1 mmol: 3~6 mL, for example, it can be 0.1 mmol: 3 mL, 0.1 mmol: 4 mL, 0.1 mmol: 5 mL or 0.1 mmol: 6 mL, etc.

[0012] In a preferred embodiment of the present invention, the solvent is acetonitrile.

[0013] In a preferred embodiment of the present invention, the ratio of cuprous iodide to hydroiodic acid is 0.1 mmol: 0.075~0.15 mL, for example, it can be 0.1 mmol: 0.75 mL, 0.1 mmol: 0.8 mL, 0.1 mmol: 0.1 mL, 0.1 mmol: 0.125 mL, or 0.1 mmol: 0.15 mL, etc.; the mass percentage concentration of hydroiodic acid is 57%.

[0014] In a preferred embodiment of the present invention, the addition of HI has a significant impact on the formation of the compound. When no concentrated HI is added, compound 1 is hardly formed. When the amount of concentrated HI added is less than 0.125 mL, other crystalline byproducts besides compound 1 are present in the product. When the amount of HI added is increased to 0.25 mL, the yield of compound 1 decreases. This is because o-phenanthroline reacts with Cu... + It has excellent binding ability; an appropriate amount of concentrated HI will inhibit Cu. + Rapid coordination with o-phenanthroline to generate byproducts, resulting in Cu + It can be oxidized to Cu under solvothermal conditions. 2+ This allows it to form target complexes with phenanthroline and iodide anions.

[0015] In a preferred embodiment of the present invention, the reaction temperature is 110~125℃, for example, 110℃, 115℃, 120℃ or 125℃, and the time is 48~96 h, for example, 48 h, 72 h or 96 h.

[0016] In a preferred embodiment of the present invention, after the reaction is completed, the temperature is reduced at a rate of 10~15 K / h (for example, 10 K / h, 11 K / h, 12 K / h, 13 K / h, 14 K / h or 15 K / h, etc.) to 25~35 ℃, for example, 25 ℃, 30 ℃ or 35 ℃, etc.

[0017] Compared with the prior art, the present invention has the following beneficial effects: This invention provides a mixture of o-phenanthroline and Cu 2+ , and I — The resulting complex is [CuI(Phen)2]·I (1, Phen = o-phenanthroline). The complex exhibits an optical absorption band spanning the ultraviolet, visible, and near-infrared regions, extending to 1600 nm, and possesses typical near-infrared broadband absorption characteristics. It shows great application potential in fields such as solar cells, broadband photodetectors, solar thermal conversion and environmental remediation, and biomedical applications. Attached Figure Description

[0018] Figure 1The PXRD diffraction pattern of compound 1 is shown below. Figure 2 This is the coordination structure diagram of compound 1; Figure 3 This is a diagram showing the π–π interaction distances between adjacent phenanthroline molecules in compound 1. Figure 4 This is a diagram of the one-dimensional supramolecular chain packing structure of compound 1; Figure 5 The experimental solid-state UV-Vis-NIR absorption spectrum of compound 1, as well as the calculated and simulated absorption spectrum and absorption lines; Figure 6 The image shows the spatial distribution and energy of the β-HOMO-5 and β-LUMO orbitals of compound 1. Detailed Implementation

[0019] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0020] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0021] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0022] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be obvious to those skilled in the art. This application specification and embodiments are merely exemplary.

[0023] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0024] The room temperature mentioned in this invention is calculated as 25±2℃.

[0025] All raw materials used in this invention can be obtained commercially or prepared using existing technologies.

[0026] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0027] Example 1 A mixture of CuI (0.1 mmol) and o-phenanthroline (0.1 mmol) was dissolved in 4 mL of acetonitrile (CH3CN), followed by the dropwise addition of 0.125 mL of concentrated HI (57% by mass). The resulting mixture was further transferred and sealed in a polytetrafluoroethylene-lined reactor, maintained at 120 °C for 72 hours, and then cooled to 30 °C at a rate of 10 K / h. Dark brown blocky crystals appeared in the product, approximately 28 mg of which (designated as compound 1) was produced, with a yield of approximately 82% (based on o-phenanthroline).

[0028] Comparative Example 1 The only difference from Example 1 is that concentrated HI is not added.

[0029] Comparative Example 2 The only difference from Example 1 is that the amount of concentrated HI added is 0.05 mL.

[0030] Comparative Example 3 The only difference from Example 1 is that the amount of concentrated HI added is 0.25 mL.

[0031] The experimental results of Examples 1 and Comparative Examples 1-3 show that the addition of concentrated HI has a significant impact on the formation of the compounds. When no concentrated HI is added, compound 1 is hardly formed. When the amount of concentrated HI added is less than 0.125 mL, other crystalline byproducts besides compound 1 are present in the product. When the amount of HI added is increased to 0.25 mL, the yield of compound 1 decreases. This is because o-phenanthroline reacts with Cu... + It has excellent binding ability; an appropriate amount of concentrated HI will inhibit Cu. + Rapid coordination with o-phenanthroline to generate byproducts, resulting in Cu + It can be oxidized to Cu under solvothermal conditions. 2+ This allows it to form target complexes with phenanthroline and iodide anions.

[0032] Test Example 1 Crystal Structure The crystallographic data of compound 1, obtained by single-crystal X-ray diffraction, are shown in the table below (Table 1).

[0033] Table 1. Crystallographic data of compound 1

[0034] Based on single-crystal X-ray diffraction (SXRD) data, compound 1 is in a triclinic crystal system. P Crystallized in space group -1, each unit cell contains six molecular formula units. Each copper ion exhibits a tetrapyramidal five-coordinate configuration, coordinated with four nitrogen atoms from two phenanthroline groups and one iodine atom. Figure 2 There is another I. — The counter anion resides in the crystal lattice. Notably, weak interactions exist between adjacent zero-dimensional complexes of o-phenanthroline molecules, with a distance of 3.529 Å between the centers of the benzene rings. Figure 3 ), thereby forming a one-dimensional supramolecular chain ( Figure 4 ).

[0035] Test Example 2 Optical Absorption Performance Under indoor lighting conditions, compound 1 appears dark brown under ambient light at room temperature. Solid-state UV-Vis-NIR absorption spectroscopy shows that the optical absorption band of compound 1 spans the UV, visible, and near-infrared regions. Figure 5 Compound 1 exhibits unusually broad optical absorption characteristics. Specifically, it possesses two main absorption bands in the ultraviolet-visible region, with absorption peaks at 413 nm and 500 nm, respectively. Furthermore, it also exhibits a broad absorption band in the near-infrared region, with a peak at 828 nm and a band edge extending consistently to 1600 nm. Based on literature review, the 413 nm and 500 nm absorption bands in the visible region can be attributed to electronic transitions from the o-phenanthroline ligand center to Cu. 2+ The charge-transfer transition to the phenanthroline ligand was investigated. The origin of the broad absorption band at 828 nm was explored through theoretical calculations. The calculation results show that compound 1 has a high oscillator intensity absorption line at 843 nm, with an oscillator intensity of 0.018. Orbital analysis shows that this transition is mainly contributed by β-HOMO-5→β-LUMO. This is combined with the specific distribution of frontier molecular orbitals in the compound structure (…). Figure 6 The absorption at 843 nm can be attributed to the coordination of iodide ions to Cu. 2+ The charge transfer transition. Therefore, the broad spectral absorption of compound 1 at 828 nm can be attributed to the coordinated iodide ion to Cu. 2+ The charge transfer transition.

[0036] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A near-infrared broadband absorbing metal complex, characterized in that, The chemical formula is [CuI(Phen)2]·I, where Phen is o-phenanthroline; The near-infrared broadband absorbing metal complex belongs to the triclinic crystal system, space group [missing information]. P -1, the unit cell parameters are: a =11.9194(3) Å, b =12.1217(3) Å, c = 23.7593(6)Å, α = 83.3830(10)°, β = 77.6190(10)°, γ = 89.6640(10)°, V =3330.03(15) Å 3 .

2. A method for preparing the near-infrared broadband absorbing metal complex according to claim 1, characterized in that, Includes the following steps: Cuprous iodide, o-phenanthroline, solvent and hydroiodic acid were mixed and reacted to obtain a near-infrared broadband absorbing metal complex.

3. The preparation method according to claim 2, characterized in that, The molar ratio of cuprous iodide to o-phenanthroline is 1:1~2.

4. The preparation method according to claim 2, characterized in that, The ratio of cuprous iodide to solvent is 0.1 mmol : 3~6 mL.

5. The preparation method according to claim 2, characterized in that, The solvent is acetonitrile.

6. The preparation method according to claim 2, characterized in that, The ratio of cuprous iodide to hydroiodic acid is 0.1 mmol : 0.075~0.15 mL; the mass percentage concentration of hydroiodic acid is 57%.

7. The preparation method according to claim 2, characterized in that, The reaction was carried out at a temperature of 110-125 °C for a time of 48-96 h.

8. The preparation method according to claim 7, characterized in that, After the reaction is complete, the temperature is reduced at a rate of 10~15 K / h to 25~35 ℃.

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